
$color: skyblue;

@function abc($canshu){
	@return $canshu/50;
}

@function yiban($canshu){
	@return $canshu/2;
}

@mixin cde($canshu,$yanse){
	border-#{$canshu}:1px solid #{$yanse};
}

.box{
	width: 100px;
	height: abc(1000px);
	background: $color;
	@include cde("bottom","tomato");
}
.pic{
	width: 1920px;
	height: 1200px;
	background-image: url(../img/57-151106135142.jpg);	
	background-size: 50%;
	background-repeat: no-repeat;

}

.pic2{
	width: yiban(1920px);
	height: yiban(1200px);
}


